This investigation is about river channels. We will be investigating the difference between a straight section and a meandering section.
Choice of Site?
The river we are studying is Millbrook, in the Ashdown forest just south of East Grinstead. The Ashdown Forrest is between 6 major roads, the A23, A272, A22, A275, A264 and the M23. This make Ashdown forest an incredibly accessible place. We decide to survey Millbrook for many reasons, the school we attend, Reigate Grammar School, is relatively close to the river, and other nearby rivers were not usable because of the foot and mouth crisis earlier in the year.
Also the river had quality’s which meant it would not be too hard to study. As we only had basic equipment, tape measure and metre rulers, if the river had been too deep or too wide we would have had a lot of trouble taking even these simple measurements. The river was also “manageable” by this I mean that the river was not too fast, if the river was too fast it could have been dangerous too stand in the river. Though these were all good reasons too study this river we wouldn’t be able to unless we gained permission from the conservators, which we had. We also studied the river in September, as this is when most rivers are at there lowest. When we arrived at the river we soon realised that not every section of the river would be suitable to study. We had to walk quite a long way up the river to find a meandering section, which was not too wide, or too overgrown with vegetation.
Our objective for this piece of work would be to gain information to answer my hypotheses. My hypotheses are:
1. Sediment will increase in width as the average depth increases.
I feel the depth of the river will cause the river to travel at a much slower rate therefore depositing the larger sediment it was carrying.
2. The smaller the channel width the greater the angle of the banks.
I feel this because the thinner a channel is that means the erosion on it will be less. There fore I believe that this will mean the banks will be steeper as they won’t have been eroded much.
3. Sediment will be closer in size in a straight section than a meandering section.
As there is more of a velocity change across a meander than a straight section, I feel that the sediment will be deposited evenly across a straight section and not so across a meander.
Intended Sequence of events
* Write an introduction explaining a little about the Millbrook and about my hypotheses.
* Go to Millbrook and collect the necessary data to answer my hypotheses.
* Write a section entitled Methods of data collection describing what method I used to collect the data.
* Place all data in a result tables and create diagrams and graphs of the data.
* Write a conclusion of my data with, accepting or rejecting.
* Write an analysis of how I could make my investigation better.